All Saints Chapel, Regensburg, 1164

Early German Romanesque

A tiny chapel that is the epitome of Romanesque architecture which led into the Renaisance. Just simple
platonic solids, cubes, spheres, octagons, laid out into a tight design of common units
without all the detailed ornamentation that came later.

I guessed at the plan from a single photo of the interior, but it's even simpler than I thought with half cyclinders attached
directly to the cube.